|Project by kinger||posted 11-17-2014 04:00 PM||4343 views||13 times favorited||23 comments|
I am fairly new to woodworking and like many of you have a small shop which for me is a one car garage that my wife very kindly lets me use for my hobby. As I have gotten more and more into the craft of woodworking and naturally started to acquire tools I recently found myself at the age old problem of dust collection. At the time I only had a Delta table saw so I decided to buy a Shop Vac from the big box store (blue variety) to use as my “dust collection” solution. It did its job OK but I had two issues with it….it was extremely loud and it was a pain to turn on and off each time I wanted to make a cut.
Doing a little research here on LJ and using my EE knowledge I came up with my own dust collection solution to address these two issues:
First was the noise. I found that many people with shop vacs had built an enclosure and padded the inside with noise dampening foam to cut the decibels down. This seemed to work for them but there was a concern with overheating the motor thus degrading the life of the vac. So what I did was build a “snorkle” for the shop vac which ported air from outside the enclosure directly to the intake for the motor cooling. So I built an enclosure out of 3/4” MDF and the noise dropped significantly.
Second was the fun part to me…..building a circuit to automatically turn on and off the shop vac. The end goal was to be able to walk up to a piece of machinery, make a cut, and have the shop vac turn on and off automatically. And since I knew I was going to be expanding my tool collection I wanted this same scenario to be true to a minimum of three tools. Skipping all the technical design and non-woodworking stuff this is what I came out with.
I have the ability to plug in three tools all of which will trigger the shop vac to turn on and off by sensing the current in the individual circuits. I can adjust the trigger sensitivity for each tool and can also adjust the lag time that the shop vac stays on once the power tool is turned off. The shop vac can be turn on separately via a side switch if I need to do a bit of shop cleaning. For the future I built in the ability to open and close blast gates depending on which tool was turned on but am still figuring out the mechanical parts (not a ME :) ). The system can switch up to a 1.5HP vac although I’d beef up the contactor to account for starting amps if that were the case. I used a 2×4 to make an enclosure and some plexi-glass to enclose the whole thing.
Works great and i’m very pleased. Thanks for looking!